JP5327110B2 - Vibration generator - Google Patents

Description

  The present invention relates to a mover and a vibration generator including a first permanent magnet and a second permanent magnet that is disposed opposite to the same pole.

  2. Description of the Related Art Conventionally, an electromagnetic induction vibration generator having a relatively simple structure is known as a power generator that converts kinetic energy into electric energy. For example, as shown in FIG. 12, a conventional vibration generator 80 includes a hollow cylindrical member 83 made of a non-magnetic material having a coil 82 arranged on the outer periphery, and a hollow inside of the cylindrical member 83 made of a permanent magnet. This utilizes the fact that an induced electromotive force is generated by the reciprocating motion of the mover 84 (see Patent Document 1).

  In such an electromagnetic induction type vibration power generator 80, since the magnetic flux density of the permanent magnet constituting the mover 84 is proportional to the induced electromotive force, a neodymium magnet having a strong magnetic force is suitable for the purpose of improving the power generation efficiency. It is used for.

Utility Model Registration No. 3026391

  However, a strong magnetic field generated from a strong permanent magnet such as a neodymium magnet leaks in a large amount to the outside of the vibration generator in the moving direction of the permanent magnet (see FIG. 4B). For this reason, for example, if the contact fitting is made of a magnetic material such as iron when it has adverse effects on peripheral objects such as magnetic recording media or the vibration generator is incorporated into an external device, the permanent magnet will There is a risk of magnetic attachment to the metal fittings.

  An object of the present invention is to provide a mover with a reduced leakage magnetic field generated from an end portion in the longitudinal direction of the mover and a vibration generator having a high induced electromotive force.

  In order to achieve the above object, a vibration generator according to a first aspect of the present invention includes a cylindrical member provided in a cylindrical casing and formed of a nonmagnetic material, and a coil disposed along the cylindrical member. And a movable element having a first permanent magnet and a second permanent magnet disposed so that the same polarity of the first permanent magnet faces each other in the cylindrical member so as to be reciprocally movable in the longitudinal direction. The second permanent magnet is formed shorter than the length of the first permanent magnet in the longitudinal direction of the tubular member, and is perpendicular to the longitudinal direction of the tubular member. In the short direction, the length of the end of the second permanent magnet on the side opposite to the side facing the first permanent magnet is longer than the length of the end of the first permanent magnet on the side facing the second permanent magnet. Is also formed short.

  In addition to the structure of the first invention, the vibration generator according to the second invention is such that the first permanent magnet and the second permanent magnet have a cylindrical shape, and are opposite to the side facing the first permanent magnet. The diameter of the end of the second permanent magnet is smaller than the diameter of the end of the first permanent magnet on the side facing the second permanent magnet.

  In addition to the second invention, the vibration generator of the third invention is such that the length of the second permanent magnet in the longitudinal direction of the cylindrical member is 90% or less of the cross-sectional radius of the first permanent magnet. , Having a length greater than zero.

  A vibration generator according to a fourth aspect of the present invention is the vibration generator according to any one of the first to third aspects, wherein the mover includes a fixing member that fixes the first permanent magnet and the second permanent magnet. The first permanent magnet and the second permanent magnet are fixed on the same axis.

  The vibration generator according to a fifth aspect of the present invention is the vibration generator according to any one of the first to fourth aspects of the invention, wherein the main body portion of the second permanent magnet has an end opposite to the end opposite to the first permanent magnet. It is formed in a taper shape toward the part.

  In addition to any of the first to fifth inventions, the vibration generator of the sixth invention is characterized in that the second permanent magnets are arranged at both ends of the first permanent magnet.

  A mover according to a seventh aspect of the present invention is a mover having a first permanent magnet and a second permanent magnet arranged so that the same poles of the first permanent magnet and the first permanent magnet are opposed to each other in the longitudinal direction of the mover. The second permanent magnet is formed to be shorter than the length of the first permanent magnet, and in the short direction perpendicular to the longitudinal direction of the mover, the second permanent magnet is opposite to the side facing the first permanent magnet. The length of the end of the two permanent magnets is shorter than the length of the end of the first permanent magnet on the side facing the second permanent magnet.

  According to the vibration generator of the first aspect of the present invention, the second permanent magnet is formed shorter than the length of the first permanent magnet in the longitudinal direction of the cylindrical member, and the short is perpendicular to the longitudinal direction of the cylindrical member. In the hand direction, the length of the end portion of the second permanent magnet opposite to the side facing the first permanent magnet is shorter than the length of the end portion of the first permanent magnet facing the second permanent magnet. Since it is formed, it is possible to obtain a vibration generator capable of reducing the leakage magnetic field in the longitudinal direction of the mover and generating a high induced electromotive force.

  According to the vibration generator of the invention of claim 2, in addition to the effect of the invention of claim 1, since the first permanent magnet and the second permanent magnet are formed in a cylindrical shape, the first permanent magnet faces the first permanent magnet. The diameter of the end portion of the second permanent magnet on the opposite side to the second permanent magnet is easier to form than the diameter of the end portion of the first permanent magnet on the side facing the second permanent magnet, and the cross-sectional shape of the cylindrical member is It is easy to make a mover close to.

  According to the vibration generator of the invention of claim 3, in addition to the effect of the invention of claim 2, the length of the second permanent magnet in the longitudinal direction of the cylindrical member is 90 of the cross-sectional radius of the first permanent magnet. % And a length greater than 0, the magnetic flux density at the same-polar facing surface of the first permanent magnet and the second permanent magnet and the magnetic flux density in the opposite direction are generated at the end of the second permanent magnet. However, a vibration generator capable of generating a higher induced electromotive force can be obtained.

  According to the vibration generator of the invention of claim 4, in addition to the effect of the invention of claim 1, the mover is a fixing member for fixing the first permanent magnet and the second permanent magnet. And the fixing member has a movable element including the same-pole opposed magnet obtained by any one of the same-pole opposed magnets that fixes the first permanent magnet and the second permanent magnet in the same axis. By making the magnetic flux density generated around the mover relatively uniform, a stable induced electromotive force can be obtained.

  According to the vibration power generator of the invention of claim 5, in addition to the effect of the invention of any one of claims 1 to 4, the main body portion of the second permanent magnet is on the side facing the first permanent magnet. Since it is formed in a tapered shape from the end portion toward the opposite end portion, a vibration generator capable of generating a higher induced electromotive force is obtained.

  According to the vibration generator of the invention of claim 6, in addition to the effect of the invention of any one of claims 1 to 5, the second permanent magnet is disposed at both ends of the first permanent magnet. The leakage magnetic field can be reduced more effectively.

  According to a mover of a seventh aspect of the present invention, there is provided a mover having a first permanent magnet and a second permanent magnet arranged so that the same poles of the first permanent magnet and the first permanent magnet are opposed to each other. In the longitudinal direction, the second permanent magnet is formed shorter than the length of the first permanent magnet, and in the lateral direction perpendicular to the longitudinal direction of the mover, the second permanent magnet faces the first permanent magnet. Since the length of the end of the second permanent magnet on the opposite side is shorter than the length of the end of the first permanent magnet on the side facing the second permanent magnet, the leakage magnetic field in the longitudinal direction of the mover Can be reduced.

It is sectional drawing of the vibration generator of 1st Embodiment of this invention. It is an expanded sectional view including the partially broken surface which expanded the needle | mover of FIG. (A) is the sectional view cut | disconnected by the 3A-3A line | wire of FIG. 2, and (B) is the 3B-3B line | wire. (A) is a figure which shows the magnetic field simulation result of the vibration generator of 1st Embodiment, (B) is a figure which shows the magnetic field simulation result of the vibration generator of the prior art which is a comparative example. It is a figure which shows the simulation result of the magnetic flux density when changing the length of the moving direction of a 2nd permanent magnet. It is a figure which shows the simulation result of the magnetic flux density when changing the length of the direction perpendicular | vertical to the moving direction of a 2nd permanent magnet. It is a figure which shows the fluid simulation result between the needle | mover and cylindrical member by having provided the 2nd permanent magnet. It is sectional drawing of the vibration generator of 2nd Embodiment of this invention. It is an expanded sectional view containing the partially broken surface which expanded the needle | mover of FIG. It is a figure which shows the simulation result of the magnetic flux density when changing the length of the direction perpendicular | vertical to the moving direction of the 2nd permanent magnet of 2nd Embodiment. It is sectional drawing of the vibration generator of 3rd Embodiment of this invention. It is sectional drawing which shows the vibration generator of a prior art.

(About the first embodiment)
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, a vibration generator 10 according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, the vibration power generator 10 includes a casing 11, a cylindrical member 190, an electromagnetic induction coil 12 wound around the outer surface of the cylindrical member 190, a first permanent magnet 130, and two second It is comprised from the needle | mover 14 provided with the permanent magnet 141,142.

  The casing 11 is formed in a cylindrical shape, and both ends thereof are open. Inside the housing 11, a cylindrical member 190 formed of a nonmagnetic material, the electromagnetic induction coil 12, and the mover 14 are provided.

  The cylindrical member 190 has a cylindrical shape and is housed and fixed inside the housing 11. In the present embodiment, the cylindrical member 190 is fixed to the casing 11 via movement restricting portions 161 and 162 that are arranged so as to cover both ends of the cylindrical member 190 and both ends of the casing 11.

  The casing 11 and the cylindrical member 190 are formed of a nonmagnetic material. For example, it is made of a resin such as acrylic, ABS, polyacetal, or polyethylene terephthalate, a ceramic such as alumina or glass, or a metal such as aluminum or brass. In the present embodiment, for example, the cylindrical member has an outer diameter of 9.0 mm, an inner diameter of 8.2 mm, and a length of about 40 mm.

  The movement restricting portions 161 and 162 are provided so that the mover 14 does not come out from the inside 180 of the cylindrical member 190. As the movement restricting portions 161 and 162, for example, flat members are provided, and are formed of acrylic resin or the like. Thereby, the inside 180 of the cylindrical member 190 is made into a sealed structure, and is blocked from outside air.

  As described above, the inside 180 of the cylindrical member 190 has a sealed structure. For example, when a neodymium magnet is used as the permanent magnet constituting the mover 14, the rust of the neodymium magnet, which is iron that is easily oxidized as a main constituent element. Can be effectively prevented. When rusting occurs, the magnetic force of the permanent magnet decreases.

  In addition, since no foreign matter is mixed into the inside 180 of the cylindrical member 190, it is possible to prevent the movement performance of the mover from being deteriorated by the foreign matter. Therefore, in order to obtain the vibration generator 10 with high reliability and stable performance, it is preferable that the inside 180 of the cylindrical member 190 has a sealed structure.

  In this embodiment, the cylindrical member 190 and the casing 11 are cylindrical, but are not limited to this shape, and may be other polygonal cylinders such as an elliptical cylinder and a square cylinder.

  The buffer members 171 and 172 are formed in a substantially cylindrical shape and are provided inside the movement restricting portions 161 and 162 in the cylindrical member 190. When the mover 14 moves inside the cylindrical member 190, the buffer members 171 and 172 contact the movement restricting portions 161 and 162 so that the end of the fixed member 20 contacts the mover 14 and the cylindrical member 190. Alternatively, it is provided to prevent the movement restricting portions 161 and 162 from being damaged.

  The buffer members 171 and 172 are made of an elastic material, and examples of the material include isobrene rubber, nitrile rubber, and butadiene rubber.

  The electromagnetic induction coil 12 is wound and fixed along the outer peripheral surface of the cylindrical member 190 in a direction orthogonal to the longitudinal direction of the outer peripheral surface of the cylindrical member 190 (X direction in FIG. 1). Both ends of the electromagnetic induction coil 12 are connected to external wiring via a rectification unit and a power storage unit (not shown). The material of the electromagnetic induction coil 12 is a copper enameled wire or the like.

  In this embodiment, in FIG. 1, the electromagnetic induction coil 12 is provided by being wound around a part of the outer surface of the cylindrical member 190, but the electromagnetic induction coil 12 is provided over the entire circumference of the cylindrical member 190. May be provided at a plurality of locations, or along the inner periphery. Here, the electromagnetic induction coil 12 is a coil of the present invention.

  As shown in FIG. 1, the mover 14 includes one first permanent magnet 130 fixed by the fixing member 20 and two second permanent magnets 141, which are arranged so that the same poles are opposed to both ends thereof. 142. The mover 14 is formed to have substantially the same size in the cross-sectional direction with respect to the inside 180 of the cylindrical member 190, and with respect to the longitudinal direction (X direction in FIG. 1) of the cylindrical member inside 180. It is formed so that it can freely reciprocate.

  The mover 14 has a cylindrical shape in this embodiment, but is not limited to this shape. However, it is desirable to have the same cross-sectional shape as the space inside the cylindrical member 180.

  In this embodiment, the mover 14 is composed of one first permanent magnet 130 and two second permanent magnets 141 and 142, and the second permanent magnets 141 and 142 are disposed at both ends of the first permanent magnet 130. ing. With such a configuration, the leakage magnetic field from both ends of the first permanent magnet 130 can be reduced as described later.

  The number of the first permanent magnets and the second permanent magnets is not particularly limited as long as the mover has the second permanent magnets having the same polarity as the first permanent magnets. One second permanent magnet may be arranged at the end of each of the two, or two or more first permanent magnets and two or more second permanent magnets may be arranged.

  The magnetization directions of the first permanent magnet 130 and the second permanent magnets 141 and 142 are the same as the moving direction (X direction in FIG. 1). As shown in FIG. The second permanent magnets 141 and 142 are formed in a cylindrical shape having through holes 156 and 157. The first permanent magnet 130 and the second permanent magnets 141 and 142 are arranged side by side in the same direction as the direction of reciprocating movement (X direction) in the interior 180 of the cylindrical member 190.

  In the present embodiment, in FIG. 2, the second permanent magnet 141 is arranged in a state of being magnetized so that the same pole is opposed to the left end portion of the first permanent magnet 130, and the second permanent magnet 141 is arranged at the right end portion of the first permanent magnet 130. Two permanent magnets 142 are arranged in a state of being magnetized so that the same poles face each other. Although it does not specifically limit as the 1st permanent magnet 130 and the 2nd permanent magnet 141,142, The neodymium magnet which shows a high magnetic force is used suitably.

  Next, the relationship between the first permanent magnet 130 and the second permanent magnets 141 and 142 will be described in more detail. The first permanent magnet 130 is a main permanent magnet constituting the mover 14, and as will be described later, second permanent magnets 141 and 142 are arranged to change the direction of the lines of magnetic force generated from the first permanent magnet 130. ing. In the present embodiment, since the two second permanent magnets 141 and 142 have the same configuration, only one second permanent magnet 141 will be described, and description of the second permanent magnet 142 will be omitted.

  In the longitudinal direction of the cylindrical member 190 (the X direction in FIGS. 1 and 2), the length L2 of the second permanent magnet 141 in FIG. 2 is formed shorter than the length L1 of the first permanent magnet. With this configuration, the leakage magnetic field generated from the mover 14 can be reduced as will be described later.

  In particular, in the present embodiment, the length L2 of the second permanent magnet 141 is preferably formed to be approximately 90% or less of the cross-sectional radius of the first permanent magnet 130. The cross-sectional radius of the first permanent magnet 130 corresponds to the diameter D1 / 2 of FIG. With this configuration, the leakage magnetic field can be further reduced as described later.

  On the other hand, in the short direction perpendicular to the longitudinal direction of the cylindrical member 190 (the Y direction in FIGS. 1 and 2), as shown in FIGS. 2 and 3, the side opposite to the side facing the first permanent magnet 130 is provided. The diameter D2 of the end portion 147 of the second permanent magnet 141 is formed to be shorter than the diameter D1 of the end portion 137 of the first permanent magnet 130 on the side facing the second permanent magnet 141.

  In the present embodiment, the diameter D1 of the end portion 137 of the first permanent magnet 130 corresponds to the length of the end portion 137 of the first permanent magnet 130 on the side facing the second permanent magnet 141 of the present invention. The diameter D2 of the end portion 147 of the second permanent magnet 141 corresponds to the length of the end portion 147 of the second permanent magnet 141 opposite to the side facing the first permanent magnet 130 of the present invention. That is, the diameter D2 of the second permanent magnet is formed smaller than the diameter D1 of the first permanent magnet.

  Further, in the mover 14, a magnetic field in the reverse direction is applied between the boundary portion where the first permanent magnet 130 and the second permanent magnet 141 are arranged to face each other and the end 147 of the second permanent magnet 141 as described later. It has occurred. Therefore, by configuring as described above, it is possible to reduce the influence that the electromotive voltage due to the magnetic flux component from the boundary portion is canceled by the counter electromotive voltage due to the reverse magnetic flux component near the end 147 of the second permanent magnet. The vibration generator 10 can generate higher induced electromotive force. This effect will be described later using simulation results.

  Next, the fixing member 20 has a cylindrical shape having brim-like locking portions at both ends, and in FIG. 1 to FIG. 3, the same poles face the first permanent magnet 130 and the second permanent magnets 141 and 142. It is provided to fix the arrangement.

  The fixing member 20 has an outer diameter smaller than the inner diameters of the through holes 135 of the first permanent magnets 130 and the through holes 156 and 157 of the second permanent magnets 141, 142. The first permanent magnet 130 and the second permanent magnets 141 and 142 are fixed so as to be concentrically inserted through the through holes 156 and 157 of the second permanent magnets 141 and 142.

  Since the first permanent magnet 130 and the second permanent magnets 141 and 142 are fixed to the same axis, as shown in FIG. 2, the second permanent magnet 141 starts from the outer peripheral portion of the end 137 of the first permanent magnet 130. It can be expected that the distance to the outer peripheral portion of the end portion 147 becomes uniform over all angles, and a substantially uniform magnetic flux density distribution is obtained as a whole in the outer peripheral direction of the end portion of the mover 14. The fixing member 20 is preferably formed of a nonmagnetic material, and examples thereof include austenitic stainless materials, aluminum alloy materials, and brass.

  Further, by making the fixing member 20 cylindrical, the movable element 14 also has a shape having a through hole 19 (see FIG. 3). In this embodiment, since the cylindrical member interior 180 is sealed, if there is no through-hole 19, the mover 14 and the cylindrical member 190 will be like a piston-like valve, and the moving speed of the mover will be reduced. There is a concern that efficiency will decrease. Therefore, when the cylindrical member interior 190 has a sealed structure, the mover 14 preferably has a through hole 19 in order to obtain high power generation efficiency.

  Note that the fixing member 20 of the present embodiment is inserted into the through holes 135 of the first permanent magnet 130 and the through holes 156 and 157 of the second permanent magnets 141 and 142, and the first permanent magnet 130 and the second permanent magnet 141, respectively. 142 is fixed, but the first permanent magnet 130 and the second permanent magnets 141 and 142 are fitted and fixed from the outside of the second permanent magnets 141 and 142 so as to be pressed by a fixing member having a U-shaped cross section. May be.

(Operation of the first embodiment)
Here, operation | movement of the vibration generator 10 of this embodiment is demonstrated using FIG. First, the vibration generator 10 is vibrated in the longitudinal direction of the cylindrical member 190 (X direction in FIG. 1). The force applied to the vibration generator 10 by the vibration is transmitted to the mover 14 as kinetic energy. The mover 14 reciprocates in the longitudinal direction inside the cylindrical member 190 and enters and leaves the space covered with the electromagnetic induction coil 12.

  When passing through the space in the electromagnetic induction coil 12, the magnetic flux lines generated from the mover 14 having the first permanent magnet 130 and the second permanent magnets 141 and 142 are orthogonal to the electromagnetic induction coil 12, An induced current is generated as an induced electromotive force. An alternating current can be generated when the mover 14 repeatedly enters and leaves the space in the electromagnetic induction coil 12.

(About the magnetic field simulation result of the mover 14)
Next, the magnetic field simulation result of the mover 14 of this embodiment will be described with reference to FIG. As shown in FIG. 4A, the vicinity of the boundary with the second permanent magnet 141 disposed so that the same pole faces the end 137 of the first permanent magnet 130 constituting the mover 14 of the present embodiment is 0. In FIG. 2, the magnetic field lines radiated from the first permanent magnet 130 and the magnetic field lines radiated from the second permanent magnet 141 repel each other, so that they are bent in a direction substantially perpendicular to the X direction as the moving direction of the mover 14. Magnetic field lines L5.

  Furthermore, the magnetic force line L6 radiated in the direction opposite to the first permanent magnet 130 from the end 147 of the second permanent magnet 141 has a short length L2 in the moving direction of the second permanent magnet 141 (see FIG. 2). The first permanent magnet 130 and the second permanent magnet 141 are attracted to a strong magnetic field in the vicinity of the boundary where they face each other. Therefore, at the end 147 of the second permanent magnet 141, the magnetic flux density of the magnetic field lines in the moving direction decreases. Thereby, the leakage magnetic field of the moving direction of the needle | mover 4 of the vibration generator 1 is reduced.

  On the other hand, in the case of the prior art movable element composed of only one permanent magnet 700, as shown in FIG. 4B, the magnetic force line L7 radiated from the end of the permanent magnet 700 spreads in the moving direction, and the movable element. It can be seen that a relatively large amount of leakage magnetic field is generated.

(Regarding the simulation result of the magnetic flux density when the length L2 of the second permanent magnet is changed)
Subsequently, a simulation result of the magnetic flux density when the length L2 of the second permanent magnet 141 of the present embodiment is changed will be described with reference to FIG. Note that this magnetic flux density is obtained by changing the length L2 (see FIG. 2) of the second permanent magnet at the position 5 mm away from the end surface 138 of the first permanent magnet 130 in FIG. 4A in the Y direction. The magnetic flux density when changing with respect to the cross-sectional radius (D1 ÷ 2) is shown. In FIG. 5, 0% on the horizontal axis is for the case where the movable element 14 is configured by only the first permanent magnet 130. The magnetic flux density of the leakage magnetic field at this time is 100% on the vertical axis, and other cases are relative. It is indicated by a numerical value.

  As shown in FIGS. 2 and 5, the length L2 of the second permanent magnet 141 is about 90% or less of the radius length (D1 / 2) of the first permanent magnet 130. When the magnetic field is large, the magnetic flux density of the leakage magnetic field is reduced to be smaller than 100%, which indicates that the movable element 14 is effective in preventing the leakage magnetic field. Therefore, the length L2 of the second permanent magnet in the moving direction (X direction) is preferably about 90% or less of the length (D1 / 2) of the cross-sectional radius of the first permanent magnet.

  Furthermore, when the length L2 of the second permanent magnet 141 is about 50 to 60% of the cross-sectional radius (D1 / 2) of the first permanent magnet 130, the magnetic flux density of the leakage magnetic field is about 20%. There is a very small value. Therefore, the length L2 of the second permanent magnet 141 in the moving direction (X direction) is more preferably 50 to 60% of the length (D1 / 2) of the cross-sectional radius of the first permanent magnet 130. The same result is obtained even when the lengths of the first permanent magnet 130 and the second permanent magnet 141 are relatively different.

(Regarding the simulation result of the magnetic flux density when the diameter D2 of the second permanent magnet is changed)
A simulation result of the magnetic flux density when the diameter D2 of the second permanent magnet 141 of the present embodiment is changed will be described with reference to FIG. In FIG. 6, the magnetic flux density on the vertical axis is a magnetic field generated outward from the mover 14 in FIG. 2 in the Y direction, and the magnetic flux density on the surface of the electromagnetic induction coil 12 is a positive value. The magnetic flux density of the generated magnetic field is negative. The numerical value on the horizontal axis is 0 on the same-pole facing surface where the first permanent magnet 130 and the second permanent magnet 141 face each other, and the numerical values “1” to “5” on the scale are the same in the X direction. A distance (mm) in a direction from the pole facing surface toward the second permanent magnet 141 is shown.

  In FIG. 6, the magnetic flux density simulation results are plotted when the ratio of the diameter D2 of the second permanent magnet to the diameter D1 of the first permanent magnet 130 is 100%, 95%, and 80%. As a comparison, a simulation result in the case of one permanent magnet as in the prior art is also plotted.

  Here, the magnetic flux density when the ratio of the diameter D2 of the second permanent magnet to the diameter D1 of the first permanent magnet 130 is 95% will be described as an example. The first permanent magnet 130 and the second permanent magnet shown in FIG. The magnetic flux density in the vicinity of the same-pole facing surface where the magnet 141 opposes (the scale on the horizontal axis in FIG. 6 is “0”) shows a positive value as in the region A surrounded by the lower right oblique line in FIG. ing.

  On the other hand, when approaching the end 147 side of the second permanent magnet 141 from the position of the same-pole facing surface in FIG. 2 (the scale on the horizontal axis in FIG. 6 is “0”), the region B is surrounded by the lower left oblique line as shown in FIG. The magnetic flux density shows a negative value. From this, it can be seen that an induced electric power having a reverse polarity is generated in the vicinity of the same-polar facing surface of the first permanent magnet 130 and the second permanent magnet 141 and in the vicinity of the end portion 147 of the second permanent magnet.

  As a result of FIG. 6, when the diameter D2 of the end portion 147 of the second permanent magnet 141 is reduced, the distance to the electromagnetic induction coil 12 is increased (see FIGS. 1 and 2), and the negative magnetic flux density component is reduced. It is shown that. Since the negative magnetic flux density component generates an electromotive voltage in the reverse direction, it is desirable to reduce the negative magnetic flux density component with respect to the magnetic flux density component in the vicinity of the same-polar facing surface that induces most of the electromotive force. If the diameter D2 of the end portion 147 of the second permanent magnet 141 is too small, the positive magnetic flux density is also small (corresponding to the region A in FIG. 6), and the total magnetic flux density may be reduced. . In this embodiment, when the diameter D2 of the end portion 147 of the second permanent magnet 141 is about 95% with respect to the diameter D1 of the end portion 137 of the first permanent magnet, the value of the magnetic flux density generated by the mover is relative. The induced electromotive force generated in the vibration power generator 10 is proportionally increased.

(About the friction reduction effect between the mover and the cylindrical member)
The fluid simulation result between the needle | mover 14 and the cylindrical member 190 by having provided the 2nd permanent magnet 141 of this embodiment using FIG. 7 is demonstrated. The horizontal axis in FIG. 7 is the ratio (%) of the diameter D2 of the end 147 of the second permanent magnet 141 to the diameter D1 of the end 137 of the first permanent magnet 130, and the vertical axis is the same as that of the mover 14 in FIG. The dynamic pressure (%) in the peripheral region of the first permanent magnet 130 between the one permanent magnets 130 is shown.

  This dynamic pressure has the same ratio of the diameter D1 of the first permanent magnet 130 and the diameter D2 of the second permanent magnet, and the dynamic pressure when the horizontal scale is 100 is 100%. Shown in relative numbers.

  As shown in FIG. 7, the diameter D1 of the first permanent magnet 130 is compared with the case where the diameter D1 of the first permanent magnet 130 and the diameter D2 of the second permanent magnet are the same (when the horizontal axis is 100%). On the other hand, when the ratio of the diameter D2 of the second permanent magnet 141 is 95%, the dynamic pressure in the peripheral region of the outer surface of the first permanent magnet 130 increases by 20% or more.

  This means that when the vibration generator 10 of the present embodiment is vibrated in the vertical direction with respect to gravity, lift is applied to the mover 4 as the moving speed of the mover 14 increases.

  That is, as a result, the friction between the mover 14 and the inside 180 of the cylindrical member 190 can be reduced, and the power generation efficiency can be improved and the life of the vibration power generator 10 can be extended. This effect is a precondition that the inside 180 of the cylindrical member 190 has a sealed structure.

  For example, in FIG. 1, when a through hole (not shown) is provided in the movement restricting portion 161 and the buffer material 171 to release the air inside the cylindrical member 190 to the outside, the movable member 14 is pushed out by the movement of the movable member 14. The air 180 inside the cylindrical member 190 is pushed out of the cylindrical member 190 through the through hole, and the momentum of the fluid fed into the space between the movable element 14 and the cylindrical member 190 is also reduced. For this reason, the lift applied to the mover 14 is also reduced, and the frictional force between the mover 14 and the cylindrical member 190 is increased, so that there is a concern that the reliability of the vibration generator is reduced.

(About the second embodiment)
Next, a vibration generator 10A according to the second embodiment will be described with reference to FIGS. The vibration power generator 10A of the second embodiment differs from the vibration power generator 10 of the first embodiment in that the mover 14 is replaced with a mover 14A. 8 and 9, the same reference numerals as those in FIGS. 1 and 2 indicate the same configuration, and the description thereof is omitted.

  The mover 14 </ b> A is arranged so that the first permanent magnet 130 of the first embodiment and the second permanent magnets 151 and 152 are opposite to each other at the opposite ends.

  As shown in FIG. 9, the second permanent magnet 151 has a main body formed in a tapered shape from an end 158 on the side facing the first permanent magnet 130 toward an end 157 on the opposite side. In addition, since the 2nd permanent magnet 151 and the 2nd permanent magnet 152 are the same structures, description of the 2nd permanent magnet 152 is abbreviate | omitted.

  As described above, when the second permanent magnets 151 and 152 are formed, the inside 180 of the cylindrical member 190 is closed by the movement restricting portions 161 and 162 as shown in FIG. Can reduce the air resistance received by the mover 14A. Further, as described below, by obtaining a higher magnetic flux density, a high induced electromotive force can be obtained in proportion thereto.

(Regarding the simulation result of the magnetic flux density when the diameter D3 of the second permanent magnet of the second embodiment is changed)
The simulation result of the magnetic flux density when the taper angle M formed in the main body portion is changed from the end portion 158 to the end portion 157 of the second permanent magnet 151 of the present embodiment will be described using FIG. In FIG. 9, the angle M is formed by an extension line in the X direction of the end portion 137 of the first permanent magnet 130 and a tapered surface formed from the end portion 158 to the end portion 157 of the second permanent magnet 151. Is the angle to be.

  In FIG. 10, the magnetic flux density on the vertical axis is a positive value on the surface of the electromagnetic induction coil 12 of the magnetic field generated outwardly in the Y direction from the mover 14A in FIG. The magnetic flux density of the generated magnetic field is negative. The numerical value on the horizontal axis is 0 on the same-polar facing surface where the first permanent magnet 130 and the second permanent magnet 151 face each other, and the numerical values of “1” to “5” on the scale are the same-polar facing surface. The distance (mm) from X to the X direction is shown.

In FIG. 10, the simulation results of the magnetic flux density are plotted when the taper angle M of the second permanent magnet 151 is 0 °, 12 °, and 27 °. As a comparison, a simulation result in the case of one permanent magnet as in the prior art is also plotted.
Here, the magnetic flux density when the angle M of the second permanent magnet 151 is 12 ° will be described as an example. The same-pole facing surface where the first permanent magnet 130 and the second permanent magnet 151 shown in FIG. The magnetic flux density in the vicinity of the position (the scale on the horizontal axis in FIG. 10 is “0”) has a positive value as in the region S surrounded by the lower right oblique line in FIG.

  On the other hand, when approaching the end 157 side of the second permanent magnet 151 from the position of the same-polarity facing surface in FIG. 2 (the scale on the horizontal axis in FIG. 10 is “0”), the region T surrounded by the lower left oblique line in FIG. As shown, the magnetic flux density shows a negative value. Therefore, in the same manner as described in the first embodiment, induction of reverse polarity is performed in the vicinity of the same-polar facing surfaces of the first permanent magnet 130 and the second permanent magnet 151 and in the vicinity of the end 157 of the second permanent magnet 151. It can be seen that power is generated.

  In this case, the distance from the end 157 of the second permanent magnet 151 to the coil 12 is increased by forming the tapered shape from the end 158 to the end 157 of the second permanent magnet 151 (FIG. 9). See), and the negative magnetic flux density component decreases.

  The difference from the first embodiment is that the length of the end 158 of the second permanent magnet 151 near the first permanent magnet 130 is the same length as the diameter D1 of the end 137 of the first permanent magnet 130. It is. Therefore, as compared with the first embodiment, even if the taper angle M is increased, the decrease in magnetic flux density near the origin is small, and the induced power generated as a vibration generator is relatively large in proportion thereto. . In the present embodiment, the value of the magnetic flux density generated by the mover when ∠M is around 12 ° is optimal, and the induced power obtained accordingly is also high.

(About the third embodiment)
Next, the structure and usage method will be described using the vibration power generator 10B of the third embodiment shown in FIG. This vibration generator 10B has a dry battery shape, and is housed in a battery housing case of an external device (not shown) such as a TV remote control or a flashlight and used as a substitute for the dry battery. In FIG. 11, the same reference numerals as those in FIGS. 1 to 3 are the same, and the description thereof is omitted.

  The external electrode has a positive electrode 21 and a negative electrode 22 and is connected to positive and negative contact fittings of a battery housing case provided in an external device (not shown). The power generated by the vibration generator 10B can be output to an external device.

  The casing 11A has a shape similar to that of a standard dry battery, and includes a cylindrical member 190 and a circuit unit 30 described below fixed therein. Both end portions of the cylindrical member 190 are hermetically fixed so as to be covered with the housing 11 </ b> A and the wall portion 210, and the circuit unit 30 is fixed to the opposite side of the wall portion 210.

  The circuit unit 30 includes a rectifier circuit, a storage circuit, and a constant voltage circuit (not shown), and these circuits are arranged on a printed board. For example, a diode bridge made of a Schottky barrier diode is used for the rectifier circuit, an electric double layer capacitor is used for the storage circuit, and a constant voltage diode is used for the constant voltage circuit.

  Then, the usage method of 10 A of vibration generators by 3rd Embodiment is demonstrated. First, the user shakes an external device in which the vibration generator 10B is incorporated. As a result, an alternating current as an induced current is generated as described above.

  The alternating current is rectified by the bridge diode, and the rectified voltage is stored up to a predetermined voltage by the power storage unit. When the user inputs a switch for operating the external device, the power of the power storage unit is output to the external device.

  When the vibration generator 10B is used in this way, iron-based materials are often used for the positive and negative contact fittings of the battery storage case of the external device. Therefore, if a magnetic field leaks from the mover 14, the mover 14 is magnetically attached to the positive and negative contact fittings of the battery housing case, and the mover 14 cannot smoothly reciprocate inside the cylindrical member 190.

  By using the mover 14 of the present invention, the magnetic field leaking from the end is reduced. That is, since the magnetic shield is provided in the moving direction (X direction in FIG. 11), the mover 14 can smoothly reciprocate inside the cylindrical member 190.

  In addition, the vibration generator 10B may be shaken before being incorporated into the external device, and after the electric power is stored in the power storage unit of the circuit unit 30, the vibration generator 10B may be incorporated into the external device and used.

  In addition, this invention is not limited to embodiment mentioned above, You may add a various change in the range which does not deviate from the summary of this indication.

  For example, the vibration generator of the present embodiment can be formed by sealing a cylindrical member in which a coil is wound and a mover reciprocates inside, but the technical idea of the present invention is based on this. Without being limited, the casing may be sealed by a casing that covers the cylindrical member and the coil.

  In the present embodiment, a ring-shaped magnetic yoke made of a ferromagnetic material may be disposed between the permanent magnets. In this case, it is desirable that the cross-sectional shape of the magnetic yoke is substantially the same as that of the permanent magnet. In addition, although not illustrated one by one, the present invention is implemented with various modifications within a range not departing from the gist thereof.

10, 10A, 10B Vibration generator 11, 11A Case 12 Electromagnetic induction coil (coil)
14, 14A Movable element 130 First permanent magnet 141, 142, 151, 152 Second permanent magnet 147 End portion 190 Cylindrical member

Claims (7)

A cylindrical member provided in a cylindrical casing and formed of a non-magnetic material;
A coil disposed along the tubular member;
A movable element provided in the cylindrical member so as to be reciprocally movable in the longitudinal direction thereof, and having a first permanent magnet and a second permanent magnet arranged so that the same polarity of the first permanent magnet faces each other. A vibration generator comprising:
In the longitudinal direction of the cylindrical member, the second permanent magnet is formed shorter than the length of the first permanent magnet,
In the short direction perpendicular to the longitudinal direction of the cylindrical member, the length of the end of the second permanent magnet opposite to the side facing the first permanent magnet is the side facing the second permanent magnet. A vibration generator characterized by being formed shorter than the length of the end of the first permanent magnet. The first permanent magnet and the second permanent magnet are cylindrical,
The diameter of the end of the second permanent magnet on the side opposite to the side facing the first permanent magnet is smaller than the diameter of the end of the first permanent magnet on the side facing the second permanent magnet. The vibration generator according to claim 1.   3. The length of the second permanent magnet in the longitudinal direction of the cylindrical member is 90% or less of the cross-sectional radius of the first permanent magnet and is longer than 0. 3. The described vibration generator.   The mover includes a fixing member that fixes the first permanent magnet and the second permanent magnet, and the fixing member fixes the first permanent magnet and the second permanent magnet in the same axis. The vibration generator according to any one of claims 1 to 3.   The main body portion of the second permanent magnet is formed in a tapered shape from an end portion on the side facing the first permanent magnet toward an end portion on the opposite side. The vibration generator according to the above.   6. The vibration generator according to claim 1, wherein the second permanent magnet is disposed at both ends of the first permanent magnet. A mover having a first permanent magnet and a second permanent magnet arranged so that the same polarity as the first permanent magnet faces each other,
In the longitudinal direction of the mover, the second permanent magnet is formed shorter than the length of the first permanent magnet,
In the short direction perpendicular to the longitudinal direction of the mover, the length of the end of the second permanent magnet opposite to the side facing the first permanent magnet is the first length on the side facing the second permanent magnet. A mover characterized in that it is formed shorter than the length of the end of one permanent magnet.